A (current versus time) graph of the current passing through a solenoi – McqOptions

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1.	A (current versus time) graph of the current passing through a solenoid is shown in figure. If the back emf at t=3s is e, find the back emf at t = 7 s
A.	\[e/2\]
B.	0
C.	\[\frac{-e}{2}\]
D.	\[-3e\]
Answer» E.

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